Defendant Jodi Arias testifies in her murder trial at Judge Sherry Stephens' Superior Court, Feb. 20, 2013. Arias is charged in the 2008 stabbing and shooting death of her ex-boyfriend, Alexander. She faces the death penalty if convicted of first-degree murder.

Jurors listening to the Jodi Arias' murder trial -- which already includes an admitted killing, confessed lies, kinky sex and nude photos -- heard another stunning allegation when the prosecution claimed that Arias sent a coded message from her jail cell in an attempt to tamper with a witness.

Prosecutor Juan Martinez delivered the bombshell during cross examination before the court halted for the weekend on Thursday, revealing two magazines that allegedly contained secret coded messages written by Arias.

Arias, 32, is on trial in Phoenix, Ariz., for allegedly murdering her ex-boyfriend Travis Alexander in 2008.

The two magazines -- an issue of Star (ironically with a cover story about Casey Anthony, to whom Arias has been compared) and an issue of Digital Photo Pro -- were intercepted by guards in August 2011 at the Estrella jail in Phoenix. Arias had intended for the two items to be handed over to Ann Campbell, a friend who has been a constant supporter and has visited Arias in jail every week, the prosecutor said.

Martinez did not reveal in court why the items drew suspicion, but at some point someone noticed the small, faint notes written in pencil in the margins.

Like something out of a spy novel, Martinez laid out for jurors what he believes is evidence of Arias' attempt to manipulate the testimony of a witness.

In the Star Magazine at the bottom of one page was the following set of numbers: 43 40 56 20 37 54. Each number, the prosecutor said, corresponded to a page from the Digital Photo Pro magazine which contained a part of the message.

Strung together, the entire message, according to Martinez, read, "You f***ed up what you told my attorney the next day / directly contradicts what I've been saying for over a year / get down here ASAP and see me before you talk to them again and before / you testify so / we can fix this / interview was excellent! Must talk ASAP!"

The intended recipient of the message remains unclear. However, based on court documents, the magazines were intercepted just a few weeks after the prosecution interviewed Arias' ex-boyfriend, Matthew McCartney, and just four days before a pre-trial hearing.

"You tried to get someone to lie at that hearing, didn't you?" Martinez asked Arias on the stand. "No," she replied.

Based on Martinez' line of questioning Thursday, it was clear the fiery prosecutor was trying to draw a link between the possible witness tampering and Arias' allegation that Alexander was sexually attracted to young boys.

Arias' claim that Alexander liked young boys bolsters the defense' case -- that Travis was a sexual deviant who was making increasingly abusive demands on Arias along with growing threats of violence. She claims she was forced to kill Alexander in self defense when he threatened to kill her.

The prosecution is hoping to convince the jury that the inflammatory testimony about pedophilia is just another one of Arias' lies.

Arias has admitted lying when she initially told police that she was not at Alexander's Mesa, Ariz., home when he was killed and lied again when she changed her story to say that a masked couple invaded Alexander's house and killed him. She claimed she lied out of shame for her actions.

While a jury might make allowances for lying in the immediate aftermath of the killing, the coded messages, if believed, indicate deception three years after the crime and could be damaging to Arias' defense.

Arias could face the death penalty if a jury convicts her of first-degree murder.

The prosecutor is expected to continue his cross-examination this morning when trial resumes for the eighth week.